Urolithiasis affects one million people annually in the United states; of these 354,000 require hospital admission. About 40% will experience a recurrence within five ears. the peak age of onset of the disease in both male and females is between 20 and 30 years. It frequently becomes a lifelong disorder requiring continued monitoring and treatment. The need for an effective treatment has prompted Costello Pharmaceutical to investigate an orally administered extract from the plan Eriobotrya japonica. In vivo studies using an animal model confirm it prevents calcium oxalate stone formation. The active moiety is a galacturonic acid containing cell wall polysaccharide. Proposed studies are locally sequenced to increase our knowledge of the extract and to provide a basis for proceeding to the next study. The studies will 1) isolate and purify the active moiety; 2) establish the chemical and structural composition of the active moiety and consequently the likelihood of synthesis and 3) prepare purified compound for future (Phase 2 SBIR) in vivo studies. The Complex Carbohydrate Research Center (CCRC) will provide guidance and assistance to us in the purification of the active moiety and will establish composition and structure of this compound at their research center.